1 /*
2 * AES-NI support functions
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 */
19
20 /*
21 * [AES-WP] https://www.intel.com/content/www/us/en/developer/articles/tool/intel-advanced-encryption-standard-aes-instructions-set.html
22 * [CLMUL-WP] https://www.intel.com/content/www/us/en/develop/download/intel-carry-less-multiplication-instruction-and-its-usage-for-computing-the-gcm-mode.html
23 */
24
25 #include "common.h"
26
27 #if defined(MBEDTLS_AESNI_C)
28
29 #include "aesni.h"
30
31 #include <string.h>
32
33 #if defined(MBEDTLS_AESNI_HAVE_CODE)
34
35 #if MBEDTLS_AESNI_HAVE_CODE == 2
36 #if !defined(_WIN32)
37 #include <cpuid.h>
38 #endif
39 #include <immintrin.h>
40 #endif
41
42 /*
43 * AES-NI support detection routine
44 */
mbedtls_aesni_has_support(unsigned int what)45 int mbedtls_aesni_has_support(unsigned int what)
46 {
47 static int done = 0;
48 static unsigned int c = 0;
49
50 if (!done) {
51 #if MBEDTLS_AESNI_HAVE_CODE == 2
52 static unsigned info[4] = { 0, 0, 0, 0 };
53 #if defined(_MSC_VER)
54 __cpuid(info, 1);
55 #else
56 __cpuid(1, info[0], info[1], info[2], info[3]);
57 #endif
58 c = info[2];
59 #else /* AESNI using asm */
60 asm ("movl $1, %%eax \n\t"
61 "cpuid \n\t"
62 : "=c" (c)
63 :
64 : "eax", "ebx", "edx");
65 #endif /* MBEDTLS_AESNI_HAVE_CODE */
66 done = 1;
67 }
68
69 return (c & what) != 0;
70 }
71
72 #if MBEDTLS_AESNI_HAVE_CODE == 2
73
74 /*
75 * AES-NI AES-ECB block en(de)cryption
76 */
mbedtls_aesni_crypt_ecb(mbedtls_aes_context * ctx,int mode,const unsigned char input[16],unsigned char output[16])77 int mbedtls_aesni_crypt_ecb(mbedtls_aes_context *ctx,
78 int mode,
79 const unsigned char input[16],
80 unsigned char output[16])
81 {
82 const __m128i *rk = (const __m128i *) (ctx->buf + ctx->rk_offset);
83 unsigned nr = ctx->nr; // Number of remaining rounds
84
85 // Load round key 0
86 __m128i state;
87 memcpy(&state, input, 16);
88 state = _mm_xor_si128(state, rk[0]); // state ^= *rk;
89 ++rk;
90 --nr;
91
92 if (mode == 0) {
93 while (nr != 0) {
94 state = _mm_aesdec_si128(state, *rk);
95 ++rk;
96 --nr;
97 }
98 state = _mm_aesdeclast_si128(state, *rk);
99 } else {
100 while (nr != 0) {
101 state = _mm_aesenc_si128(state, *rk);
102 ++rk;
103 --nr;
104 }
105 state = _mm_aesenclast_si128(state, *rk);
106 }
107
108 memcpy(output, &state, 16);
109 return 0;
110 }
111
112 /*
113 * GCM multiplication: c = a times b in GF(2^128)
114 * Based on [CLMUL-WP] algorithms 1 (with equation 27) and 5.
115 */
116
gcm_clmul(const __m128i aa,const __m128i bb,__m128i * cc,__m128i * dd)117 static void gcm_clmul(const __m128i aa, const __m128i bb,
118 __m128i *cc, __m128i *dd)
119 {
120 /*
121 * Caryless multiplication dd:cc = aa * bb
122 * using [CLMUL-WP] algorithm 1 (p. 12).
123 */
124 *cc = _mm_clmulepi64_si128(aa, bb, 0x00); // a0*b0 = c1:c0
125 *dd = _mm_clmulepi64_si128(aa, bb, 0x11); // a1*b1 = d1:d0
126 __m128i ee = _mm_clmulepi64_si128(aa, bb, 0x10); // a0*b1 = e1:e0
127 __m128i ff = _mm_clmulepi64_si128(aa, bb, 0x01); // a1*b0 = f1:f0
128 ff = _mm_xor_si128(ff, ee); // e1+f1:e0+f0
129 ee = ff; // e1+f1:e0+f0
130 ff = _mm_srli_si128(ff, 8); // 0:e1+f1
131 ee = _mm_slli_si128(ee, 8); // e0+f0:0
132 *dd = _mm_xor_si128(*dd, ff); // d1:d0+e1+f1
133 *cc = _mm_xor_si128(*cc, ee); // c1+e0+f0:c0
134 }
135
gcm_shift(__m128i * cc,__m128i * dd)136 static void gcm_shift(__m128i *cc, __m128i *dd)
137 {
138 /* [CMUCL-WP] Algorithm 5 Step 1: shift cc:dd one bit to the left,
139 * taking advantage of [CLMUL-WP] eq 27 (p. 18). */
140 // // *cc = r1:r0
141 // // *dd = r3:r2
142 __m128i cc_lo = _mm_slli_epi64(*cc, 1); // r1<<1:r0<<1
143 __m128i dd_lo = _mm_slli_epi64(*dd, 1); // r3<<1:r2<<1
144 __m128i cc_hi = _mm_srli_epi64(*cc, 63); // r1>>63:r0>>63
145 __m128i dd_hi = _mm_srli_epi64(*dd, 63); // r3>>63:r2>>63
146 __m128i xmm5 = _mm_srli_si128(cc_hi, 8); // 0:r1>>63
147 cc_hi = _mm_slli_si128(cc_hi, 8); // r0>>63:0
148 dd_hi = _mm_slli_si128(dd_hi, 8); // 0:r1>>63
149
150 *cc = _mm_or_si128(cc_lo, cc_hi); // r1<<1|r0>>63:r0<<1
151 *dd = _mm_or_si128(_mm_or_si128(dd_lo, dd_hi), xmm5); // r3<<1|r2>>62:r2<<1|r1>>63
152 }
153
gcm_reduce(__m128i xx)154 static __m128i gcm_reduce(__m128i xx)
155 {
156 // // xx = x1:x0
157 /* [CLMUL-WP] Algorithm 5 Step 2 */
158 __m128i aa = _mm_slli_epi64(xx, 63); // x1<<63:x0<<63 = stuff:a
159 __m128i bb = _mm_slli_epi64(xx, 62); // x1<<62:x0<<62 = stuff:b
160 __m128i cc = _mm_slli_epi64(xx, 57); // x1<<57:x0<<57 = stuff:c
161 __m128i dd = _mm_slli_si128(_mm_xor_si128(_mm_xor_si128(aa, bb), cc), 8); // a+b+c:0
162 return _mm_xor_si128(dd, xx); // x1+a+b+c:x0 = d:x0
163 }
164
gcm_mix(__m128i dx)165 static __m128i gcm_mix(__m128i dx)
166 {
167 /* [CLMUL-WP] Algorithm 5 Steps 3 and 4 */
168 __m128i ee = _mm_srli_epi64(dx, 1); // e1:x0>>1 = e1:e0'
169 __m128i ff = _mm_srli_epi64(dx, 2); // f1:x0>>2 = f1:f0'
170 __m128i gg = _mm_srli_epi64(dx, 7); // g1:x0>>7 = g1:g0'
171
172 // e0'+f0'+g0' is almost e0+f0+g0, except for some missing
173 // bits carried from d. Now get those bits back in.
174 __m128i eh = _mm_slli_epi64(dx, 63); // d<<63:stuff
175 __m128i fh = _mm_slli_epi64(dx, 62); // d<<62:stuff
176 __m128i gh = _mm_slli_epi64(dx, 57); // d<<57:stuff
177 __m128i hh = _mm_srli_si128(_mm_xor_si128(_mm_xor_si128(eh, fh), gh), 8); // 0:missing bits of d
178
179 return _mm_xor_si128(_mm_xor_si128(_mm_xor_si128(_mm_xor_si128(ee, ff), gg), hh), dx);
180 }
181
mbedtls_aesni_gcm_mult(unsigned char c[16],const unsigned char a[16],const unsigned char b[16])182 void mbedtls_aesni_gcm_mult(unsigned char c[16],
183 const unsigned char a[16],
184 const unsigned char b[16])
185 {
186 __m128i aa, bb, cc, dd;
187
188 /* The inputs are in big-endian order, so byte-reverse them */
189 for (size_t i = 0; i < 16; i++) {
190 ((uint8_t *) &aa)[i] = a[15 - i];
191 ((uint8_t *) &bb)[i] = b[15 - i];
192 }
193
194 gcm_clmul(aa, bb, &cc, &dd);
195 gcm_shift(&cc, &dd);
196 /*
197 * Now reduce modulo the GCM polynomial x^128 + x^7 + x^2 + x + 1
198 * using [CLMUL-WP] algorithm 5 (p. 18).
199 * Currently dd:cc holds x3:x2:x1:x0 (already shifted).
200 */
201 __m128i dx = gcm_reduce(cc);
202 __m128i xh = gcm_mix(dx);
203 cc = _mm_xor_si128(xh, dd); // x3+h1:x2+h0
204
205 /* Now byte-reverse the outputs */
206 for (size_t i = 0; i < 16; i++) {
207 c[i] = ((uint8_t *) &cc)[15 - i];
208 }
209
210 return;
211 }
212
213 /*
214 * Compute decryption round keys from encryption round keys
215 */
mbedtls_aesni_inverse_key(unsigned char * invkey,const unsigned char * fwdkey,int nr)216 void mbedtls_aesni_inverse_key(unsigned char *invkey,
217 const unsigned char *fwdkey, int nr)
218 {
219 __m128i *ik = (__m128i *) invkey;
220 const __m128i *fk = (const __m128i *) fwdkey + nr;
221
222 *ik = *fk;
223 for (--fk, ++ik; fk > (const __m128i *) fwdkey; --fk, ++ik) {
224 *ik = _mm_aesimc_si128(*fk);
225 }
226 *ik = *fk;
227 }
228
229 /*
230 * Key expansion, 128-bit case
231 */
aesni_set_rk_128(__m128i state,__m128i xword)232 static __m128i aesni_set_rk_128(__m128i state, __m128i xword)
233 {
234 /*
235 * Finish generating the next round key.
236 *
237 * On entry state is r3:r2:r1:r0 and xword is X:stuff:stuff:stuff
238 * with X = rot( sub( r3 ) ) ^ RCON (obtained with AESKEYGENASSIST).
239 *
240 * On exit, xword is r7:r6:r5:r4
241 * with r4 = X + r0, r5 = r4 + r1, r6 = r5 + r2, r7 = r6 + r3
242 * and this is returned, to be written to the round key buffer.
243 */
244 xword = _mm_shuffle_epi32(xword, 0xff); // X:X:X:X
245 xword = _mm_xor_si128(xword, state); // X+r3:X+r2:X+r1:r4
246 state = _mm_slli_si128(state, 4); // r2:r1:r0:0
247 xword = _mm_xor_si128(xword, state); // X+r3+r2:X+r2+r1:r5:r4
248 state = _mm_slli_si128(state, 4); // r1:r0:0:0
249 xword = _mm_xor_si128(xword, state); // X+r3+r2+r1:r6:r5:r4
250 state = _mm_slli_si128(state, 4); // r0:0:0:0
251 state = _mm_xor_si128(xword, state); // r7:r6:r5:r4
252 return state;
253 }
254
aesni_setkey_enc_128(unsigned char * rk_bytes,const unsigned char * key)255 static void aesni_setkey_enc_128(unsigned char *rk_bytes,
256 const unsigned char *key)
257 {
258 __m128i *rk = (__m128i *) rk_bytes;
259
260 memcpy(&rk[0], key, 16);
261 rk[1] = aesni_set_rk_128(rk[0], _mm_aeskeygenassist_si128(rk[0], 0x01));
262 rk[2] = aesni_set_rk_128(rk[1], _mm_aeskeygenassist_si128(rk[1], 0x02));
263 rk[3] = aesni_set_rk_128(rk[2], _mm_aeskeygenassist_si128(rk[2], 0x04));
264 rk[4] = aesni_set_rk_128(rk[3], _mm_aeskeygenassist_si128(rk[3], 0x08));
265 rk[5] = aesni_set_rk_128(rk[4], _mm_aeskeygenassist_si128(rk[4], 0x10));
266 rk[6] = aesni_set_rk_128(rk[5], _mm_aeskeygenassist_si128(rk[5], 0x20));
267 rk[7] = aesni_set_rk_128(rk[6], _mm_aeskeygenassist_si128(rk[6], 0x40));
268 rk[8] = aesni_set_rk_128(rk[7], _mm_aeskeygenassist_si128(rk[7], 0x80));
269 rk[9] = aesni_set_rk_128(rk[8], _mm_aeskeygenassist_si128(rk[8], 0x1B));
270 rk[10] = aesni_set_rk_128(rk[9], _mm_aeskeygenassist_si128(rk[9], 0x36));
271 }
272
273 /*
274 * Key expansion, 192-bit case
275 */
aesni_set_rk_192(__m128i * state0,__m128i * state1,__m128i xword,unsigned char * rk)276 static void aesni_set_rk_192(__m128i *state0, __m128i *state1, __m128i xword,
277 unsigned char *rk)
278 {
279 /*
280 * Finish generating the next 6 quarter-keys.
281 *
282 * On entry state0 is r3:r2:r1:r0, state1 is stuff:stuff:r5:r4
283 * and xword is stuff:stuff:X:stuff with X = rot( sub( r3 ) ) ^ RCON
284 * (obtained with AESKEYGENASSIST).
285 *
286 * On exit, state0 is r9:r8:r7:r6 and state1 is stuff:stuff:r11:r10
287 * and those are written to the round key buffer.
288 */
289 xword = _mm_shuffle_epi32(xword, 0x55); // X:X:X:X
290 xword = _mm_xor_si128(xword, *state0); // X+r3:X+r2:X+r1:X+r0
291 *state0 = _mm_slli_si128(*state0, 4); // r2:r1:r0:0
292 xword = _mm_xor_si128(xword, *state0); // X+r3+r2:X+r2+r1:X+r1+r0:X+r0
293 *state0 = _mm_slli_si128(*state0, 4); // r1:r0:0:0
294 xword = _mm_xor_si128(xword, *state0); // X+r3+r2+r1:X+r2+r1+r0:X+r1+r0:X+r0
295 *state0 = _mm_slli_si128(*state0, 4); // r0:0:0:0
296 xword = _mm_xor_si128(xword, *state0); // X+r3+r2+r1+r0:X+r2+r1+r0:X+r1+r0:X+r0
297 *state0 = xword; // = r9:r8:r7:r6
298
299 xword = _mm_shuffle_epi32(xword, 0xff); // r9:r9:r9:r9
300 xword = _mm_xor_si128(xword, *state1); // stuff:stuff:r9+r5:r9+r4
301 *state1 = _mm_slli_si128(*state1, 4); // stuff:stuff:r4:0
302 xword = _mm_xor_si128(xword, *state1); // stuff:stuff:r9+r5+r4:r9+r4
303 *state1 = xword; // = stuff:stuff:r11:r10
304
305 /* Store state0 and the low half of state1 into rk, which is conceptually
306 * an array of 24-byte elements. Since 24 is not a multiple of 16,
307 * rk is not necessarily aligned so just `*rk = *state0` doesn't work. */
308 memcpy(rk, state0, 16);
309 memcpy(rk + 16, state1, 8);
310 }
311
aesni_setkey_enc_192(unsigned char * rk,const unsigned char * key)312 static void aesni_setkey_enc_192(unsigned char *rk,
313 const unsigned char *key)
314 {
315 /* First round: use original key */
316 memcpy(rk, key, 24);
317 /* aes.c guarantees that rk is aligned on a 16-byte boundary. */
318 __m128i state0 = ((__m128i *) rk)[0];
319 __m128i state1 = _mm_loadl_epi64(((__m128i *) rk) + 1);
320
321 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x01), rk + 24 * 1);
322 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x02), rk + 24 * 2);
323 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x04), rk + 24 * 3);
324 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x08), rk + 24 * 4);
325 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x10), rk + 24 * 5);
326 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x20), rk + 24 * 6);
327 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x40), rk + 24 * 7);
328 aesni_set_rk_192(&state0, &state1, _mm_aeskeygenassist_si128(state1, 0x80), rk + 24 * 8);
329 }
330
331 /*
332 * Key expansion, 256-bit case
333 */
aesni_set_rk_256(__m128i state0,__m128i state1,__m128i xword,__m128i * rk0,__m128i * rk1)334 static void aesni_set_rk_256(__m128i state0, __m128i state1, __m128i xword,
335 __m128i *rk0, __m128i *rk1)
336 {
337 /*
338 * Finish generating the next two round keys.
339 *
340 * On entry state0 is r3:r2:r1:r0, state1 is r7:r6:r5:r4 and
341 * xword is X:stuff:stuff:stuff with X = rot( sub( r7 )) ^ RCON
342 * (obtained with AESKEYGENASSIST).
343 *
344 * On exit, *rk0 is r11:r10:r9:r8 and *rk1 is r15:r14:r13:r12
345 */
346 xword = _mm_shuffle_epi32(xword, 0xff);
347 xword = _mm_xor_si128(xword, state0);
348 state0 = _mm_slli_si128(state0, 4);
349 xword = _mm_xor_si128(xword, state0);
350 state0 = _mm_slli_si128(state0, 4);
351 xword = _mm_xor_si128(xword, state0);
352 state0 = _mm_slli_si128(state0, 4);
353 state0 = _mm_xor_si128(state0, xword);
354 *rk0 = state0;
355
356 /* Set xword to stuff:Y:stuff:stuff with Y = subword( r11 )
357 * and proceed to generate next round key from there */
358 xword = _mm_aeskeygenassist_si128(state0, 0x00);
359 xword = _mm_shuffle_epi32(xword, 0xaa);
360 xword = _mm_xor_si128(xword, state1);
361 state1 = _mm_slli_si128(state1, 4);
362 xword = _mm_xor_si128(xword, state1);
363 state1 = _mm_slli_si128(state1, 4);
364 xword = _mm_xor_si128(xword, state1);
365 state1 = _mm_slli_si128(state1, 4);
366 state1 = _mm_xor_si128(state1, xword);
367 *rk1 = state1;
368 }
369
aesni_setkey_enc_256(unsigned char * rk_bytes,const unsigned char * key)370 static void aesni_setkey_enc_256(unsigned char *rk_bytes,
371 const unsigned char *key)
372 {
373 __m128i *rk = (__m128i *) rk_bytes;
374
375 memcpy(&rk[0], key, 16);
376 memcpy(&rk[1], key + 16, 16);
377
378 /*
379 * Main "loop" - Generating one more key than necessary,
380 * see definition of mbedtls_aes_context.buf
381 */
382 aesni_set_rk_256(rk[0], rk[1], _mm_aeskeygenassist_si128(rk[1], 0x01), &rk[2], &rk[3]);
383 aesni_set_rk_256(rk[2], rk[3], _mm_aeskeygenassist_si128(rk[3], 0x02), &rk[4], &rk[5]);
384 aesni_set_rk_256(rk[4], rk[5], _mm_aeskeygenassist_si128(rk[5], 0x04), &rk[6], &rk[7]);
385 aesni_set_rk_256(rk[6], rk[7], _mm_aeskeygenassist_si128(rk[7], 0x08), &rk[8], &rk[9]);
386 aesni_set_rk_256(rk[8], rk[9], _mm_aeskeygenassist_si128(rk[9], 0x10), &rk[10], &rk[11]);
387 aesni_set_rk_256(rk[10], rk[11], _mm_aeskeygenassist_si128(rk[11], 0x20), &rk[12], &rk[13]);
388 aesni_set_rk_256(rk[12], rk[13], _mm_aeskeygenassist_si128(rk[13], 0x40), &rk[14], &rk[15]);
389 }
390
391 #else /* MBEDTLS_AESNI_HAVE_CODE == 1 */
392
393 #if defined(__has_feature)
394 #if __has_feature(memory_sanitizer)
395 #warning \
396 "MBEDTLS_AESNI_C is known to cause spurious error reports with some memory sanitizers as they do not understand the assembly code."
397 #endif
398 #endif
399
400 /*
401 * Binutils needs to be at least 2.19 to support AES-NI instructions.
402 * Unfortunately, a lot of users have a lower version now (2014-04).
403 * Emit bytecode directly in order to support "old" version of gas.
404 *
405 * Opcodes from the Intel architecture reference manual, vol. 3.
406 * We always use registers, so we don't need prefixes for memory operands.
407 * Operand macros are in gas order (src, dst) as opposed to Intel order
408 * (dst, src) in order to blend better into the surrounding assembly code.
409 */
410 #define AESDEC(regs) ".byte 0x66,0x0F,0x38,0xDE," regs "\n\t"
411 #define AESDECLAST(regs) ".byte 0x66,0x0F,0x38,0xDF," regs "\n\t"
412 #define AESENC(regs) ".byte 0x66,0x0F,0x38,0xDC," regs "\n\t"
413 #define AESENCLAST(regs) ".byte 0x66,0x0F,0x38,0xDD," regs "\n\t"
414 #define AESIMC(regs) ".byte 0x66,0x0F,0x38,0xDB," regs "\n\t"
415 #define AESKEYGENA(regs, imm) ".byte 0x66,0x0F,0x3A,0xDF," regs "," imm "\n\t"
416 #define PCLMULQDQ(regs, imm) ".byte 0x66,0x0F,0x3A,0x44," regs "," imm "\n\t"
417
418 #define xmm0_xmm0 "0xC0"
419 #define xmm0_xmm1 "0xC8"
420 #define xmm0_xmm2 "0xD0"
421 #define xmm0_xmm3 "0xD8"
422 #define xmm0_xmm4 "0xE0"
423 #define xmm1_xmm0 "0xC1"
424 #define xmm1_xmm2 "0xD1"
425
426 /*
427 * AES-NI AES-ECB block en(de)cryption
428 */
mbedtls_aesni_crypt_ecb(mbedtls_aes_context * ctx,int mode,const unsigned char input[16],unsigned char output[16])429 int mbedtls_aesni_crypt_ecb(mbedtls_aes_context *ctx,
430 int mode,
431 const unsigned char input[16],
432 unsigned char output[16])
433 {
434 asm ("movdqu (%3), %%xmm0 \n\t" // load input
435 "movdqu (%1), %%xmm1 \n\t" // load round key 0
436 "pxor %%xmm1, %%xmm0 \n\t" // round 0
437 "add $16, %1 \n\t" // point to next round key
438 "subl $1, %0 \n\t" // normal rounds = nr - 1
439 "test %2, %2 \n\t" // mode?
440 "jz 2f \n\t" // 0 = decrypt
441
442 "1: \n\t" // encryption loop
443 "movdqu (%1), %%xmm1 \n\t" // load round key
444 AESENC(xmm1_xmm0) // do round
445 "add $16, %1 \n\t" // point to next round key
446 "subl $1, %0 \n\t" // loop
447 "jnz 1b \n\t"
448 "movdqu (%1), %%xmm1 \n\t" // load round key
449 AESENCLAST(xmm1_xmm0) // last round
450 "jmp 3f \n\t"
451
452 "2: \n\t" // decryption loop
453 "movdqu (%1), %%xmm1 \n\t"
454 AESDEC(xmm1_xmm0) // do round
455 "add $16, %1 \n\t"
456 "subl $1, %0 \n\t"
457 "jnz 2b \n\t"
458 "movdqu (%1), %%xmm1 \n\t" // load round key
459 AESDECLAST(xmm1_xmm0) // last round
460
461 "3: \n\t"
462 "movdqu %%xmm0, (%4) \n\t" // export output
463 :
464 : "r" (ctx->nr), "r" (ctx->buf + ctx->rk_offset), "r" (mode), "r" (input), "r" (output)
465 : "memory", "cc", "xmm0", "xmm1");
466
467
468 return 0;
469 }
470
471 /*
472 * GCM multiplication: c = a times b in GF(2^128)
473 * Based on [CLMUL-WP] algorithms 1 (with equation 27) and 5.
474 */
mbedtls_aesni_gcm_mult(unsigned char c[16],const unsigned char a[16],const unsigned char b[16])475 void mbedtls_aesni_gcm_mult(unsigned char c[16],
476 const unsigned char a[16],
477 const unsigned char b[16])
478 {
479 unsigned char aa[16], bb[16], cc[16];
480 size_t i;
481
482 /* The inputs are in big-endian order, so byte-reverse them */
483 for (i = 0; i < 16; i++) {
484 aa[i] = a[15 - i];
485 bb[i] = b[15 - i];
486 }
487
488 asm ("movdqu (%0), %%xmm0 \n\t" // a1:a0
489 "movdqu (%1), %%xmm1 \n\t" // b1:b0
490
491 /*
492 * Caryless multiplication xmm2:xmm1 = xmm0 * xmm1
493 * using [CLMUL-WP] algorithm 1 (p. 12).
494 */
495 "movdqa %%xmm1, %%xmm2 \n\t" // copy of b1:b0
496 "movdqa %%xmm1, %%xmm3 \n\t" // same
497 "movdqa %%xmm1, %%xmm4 \n\t" // same
498 PCLMULQDQ(xmm0_xmm1, "0x00") // a0*b0 = c1:c0
499 PCLMULQDQ(xmm0_xmm2, "0x11") // a1*b1 = d1:d0
500 PCLMULQDQ(xmm0_xmm3, "0x10") // a0*b1 = e1:e0
501 PCLMULQDQ(xmm0_xmm4, "0x01") // a1*b0 = f1:f0
502 "pxor %%xmm3, %%xmm4 \n\t" // e1+f1:e0+f0
503 "movdqa %%xmm4, %%xmm3 \n\t" // same
504 "psrldq $8, %%xmm4 \n\t" // 0:e1+f1
505 "pslldq $8, %%xmm3 \n\t" // e0+f0:0
506 "pxor %%xmm4, %%xmm2 \n\t" // d1:d0+e1+f1
507 "pxor %%xmm3, %%xmm1 \n\t" // c1+e0+f1:c0
508
509 /*
510 * Now shift the result one bit to the left,
511 * taking advantage of [CLMUL-WP] eq 27 (p. 18)
512 */
513 "movdqa %%xmm1, %%xmm3 \n\t" // r1:r0
514 "movdqa %%xmm2, %%xmm4 \n\t" // r3:r2
515 "psllq $1, %%xmm1 \n\t" // r1<<1:r0<<1
516 "psllq $1, %%xmm2 \n\t" // r3<<1:r2<<1
517 "psrlq $63, %%xmm3 \n\t" // r1>>63:r0>>63
518 "psrlq $63, %%xmm4 \n\t" // r3>>63:r2>>63
519 "movdqa %%xmm3, %%xmm5 \n\t" // r1>>63:r0>>63
520 "pslldq $8, %%xmm3 \n\t" // r0>>63:0
521 "pslldq $8, %%xmm4 \n\t" // r2>>63:0
522 "psrldq $8, %%xmm5 \n\t" // 0:r1>>63
523 "por %%xmm3, %%xmm1 \n\t" // r1<<1|r0>>63:r0<<1
524 "por %%xmm4, %%xmm2 \n\t" // r3<<1|r2>>62:r2<<1
525 "por %%xmm5, %%xmm2 \n\t" // r3<<1|r2>>62:r2<<1|r1>>63
526
527 /*
528 * Now reduce modulo the GCM polynomial x^128 + x^7 + x^2 + x + 1
529 * using [CLMUL-WP] algorithm 5 (p. 18).
530 * Currently xmm2:xmm1 holds x3:x2:x1:x0 (already shifted).
531 */
532 /* Step 2 (1) */
533 "movdqa %%xmm1, %%xmm3 \n\t" // x1:x0
534 "movdqa %%xmm1, %%xmm4 \n\t" // same
535 "movdqa %%xmm1, %%xmm5 \n\t" // same
536 "psllq $63, %%xmm3 \n\t" // x1<<63:x0<<63 = stuff:a
537 "psllq $62, %%xmm4 \n\t" // x1<<62:x0<<62 = stuff:b
538 "psllq $57, %%xmm5 \n\t" // x1<<57:x0<<57 = stuff:c
539
540 /* Step 2 (2) */
541 "pxor %%xmm4, %%xmm3 \n\t" // stuff:a+b
542 "pxor %%xmm5, %%xmm3 \n\t" // stuff:a+b+c
543 "pslldq $8, %%xmm3 \n\t" // a+b+c:0
544 "pxor %%xmm3, %%xmm1 \n\t" // x1+a+b+c:x0 = d:x0
545
546 /* Steps 3 and 4 */
547 "movdqa %%xmm1,%%xmm0 \n\t" // d:x0
548 "movdqa %%xmm1,%%xmm4 \n\t" // same
549 "movdqa %%xmm1,%%xmm5 \n\t" // same
550 "psrlq $1, %%xmm0 \n\t" // e1:x0>>1 = e1:e0'
551 "psrlq $2, %%xmm4 \n\t" // f1:x0>>2 = f1:f0'
552 "psrlq $7, %%xmm5 \n\t" // g1:x0>>7 = g1:g0'
553 "pxor %%xmm4, %%xmm0 \n\t" // e1+f1:e0'+f0'
554 "pxor %%xmm5, %%xmm0 \n\t" // e1+f1+g1:e0'+f0'+g0'
555 // e0'+f0'+g0' is almost e0+f0+g0, ex\tcept for some missing
556 // bits carried from d. Now get those\t bits back in.
557 "movdqa %%xmm1,%%xmm3 \n\t" // d:x0
558 "movdqa %%xmm1,%%xmm4 \n\t" // same
559 "movdqa %%xmm1,%%xmm5 \n\t" // same
560 "psllq $63, %%xmm3 \n\t" // d<<63:stuff
561 "psllq $62, %%xmm4 \n\t" // d<<62:stuff
562 "psllq $57, %%xmm5 \n\t" // d<<57:stuff
563 "pxor %%xmm4, %%xmm3 \n\t" // d<<63+d<<62:stuff
564 "pxor %%xmm5, %%xmm3 \n\t" // missing bits of d:stuff
565 "psrldq $8, %%xmm3 \n\t" // 0:missing bits of d
566 "pxor %%xmm3, %%xmm0 \n\t" // e1+f1+g1:e0+f0+g0
567 "pxor %%xmm1, %%xmm0 \n\t" // h1:h0
568 "pxor %%xmm2, %%xmm0 \n\t" // x3+h1:x2+h0
569
570 "movdqu %%xmm0, (%2) \n\t" // done
571 :
572 : "r" (aa), "r" (bb), "r" (cc)
573 : "memory", "cc", "xmm0", "xmm1", "xmm2", "xmm3", "xmm4", "xmm5");
574
575 /* Now byte-reverse the outputs */
576 for (i = 0; i < 16; i++) {
577 c[i] = cc[15 - i];
578 }
579
580 return;
581 }
582
583 /*
584 * Compute decryption round keys from encryption round keys
585 */
mbedtls_aesni_inverse_key(unsigned char * invkey,const unsigned char * fwdkey,int nr)586 void mbedtls_aesni_inverse_key(unsigned char *invkey,
587 const unsigned char *fwdkey, int nr)
588 {
589 unsigned char *ik = invkey;
590 const unsigned char *fk = fwdkey + 16 * nr;
591
592 memcpy(ik, fk, 16);
593
594 for (fk -= 16, ik += 16; fk > fwdkey; fk -= 16, ik += 16) {
595 asm ("movdqu (%0), %%xmm0 \n\t"
596 AESIMC(xmm0_xmm0)
597 "movdqu %%xmm0, (%1) \n\t"
598 :
599 : "r" (fk), "r" (ik)
600 : "memory", "xmm0");
601 }
602
603 memcpy(ik, fk, 16);
604 }
605
606 /*
607 * Key expansion, 128-bit case
608 */
aesni_setkey_enc_128(unsigned char * rk,const unsigned char * key)609 static void aesni_setkey_enc_128(unsigned char *rk,
610 const unsigned char *key)
611 {
612 asm ("movdqu (%1), %%xmm0 \n\t" // copy the original key
613 "movdqu %%xmm0, (%0) \n\t" // as round key 0
614 "jmp 2f \n\t" // skip auxiliary routine
615
616 /*
617 * Finish generating the next round key.
618 *
619 * On entry xmm0 is r3:r2:r1:r0 and xmm1 is X:stuff:stuff:stuff
620 * with X = rot( sub( r3 ) ) ^ RCON.
621 *
622 * On exit, xmm0 is r7:r6:r5:r4
623 * with r4 = X + r0, r5 = r4 + r1, r6 = r5 + r2, r7 = r6 + r3
624 * and those are written to the round key buffer.
625 */
626 "1: \n\t"
627 "pshufd $0xff, %%xmm1, %%xmm1 \n\t" // X:X:X:X
628 "pxor %%xmm0, %%xmm1 \n\t" // X+r3:X+r2:X+r1:r4
629 "pslldq $4, %%xmm0 \n\t" // r2:r1:r0:0
630 "pxor %%xmm0, %%xmm1 \n\t" // X+r3+r2:X+r2+r1:r5:r4
631 "pslldq $4, %%xmm0 \n\t" // etc
632 "pxor %%xmm0, %%xmm1 \n\t"
633 "pslldq $4, %%xmm0 \n\t"
634 "pxor %%xmm1, %%xmm0 \n\t" // update xmm0 for next time!
635 "add $16, %0 \n\t" // point to next round key
636 "movdqu %%xmm0, (%0) \n\t" // write it
637 "ret \n\t"
638
639 /* Main "loop" */
640 "2: \n\t"
641 AESKEYGENA(xmm0_xmm1, "0x01") "call 1b \n\t"
642 AESKEYGENA(xmm0_xmm1, "0x02") "call 1b \n\t"
643 AESKEYGENA(xmm0_xmm1, "0x04") "call 1b \n\t"
644 AESKEYGENA(xmm0_xmm1, "0x08") "call 1b \n\t"
645 AESKEYGENA(xmm0_xmm1, "0x10") "call 1b \n\t"
646 AESKEYGENA(xmm0_xmm1, "0x20") "call 1b \n\t"
647 AESKEYGENA(xmm0_xmm1, "0x40") "call 1b \n\t"
648 AESKEYGENA(xmm0_xmm1, "0x80") "call 1b \n\t"
649 AESKEYGENA(xmm0_xmm1, "0x1B") "call 1b \n\t"
650 AESKEYGENA(xmm0_xmm1, "0x36") "call 1b \n\t"
651 :
652 : "r" (rk), "r" (key)
653 : "memory", "cc", "0");
654 }
655
656 /*
657 * Key expansion, 192-bit case
658 */
aesni_setkey_enc_192(unsigned char * rk,const unsigned char * key)659 static void aesni_setkey_enc_192(unsigned char *rk,
660 const unsigned char *key)
661 {
662 asm ("movdqu (%1), %%xmm0 \n\t" // copy original round key
663 "movdqu %%xmm0, (%0) \n\t"
664 "add $16, %0 \n\t"
665 "movq 16(%1), %%xmm1 \n\t"
666 "movq %%xmm1, (%0) \n\t"
667 "add $8, %0 \n\t"
668 "jmp 2f \n\t" // skip auxiliary routine
669
670 /*
671 * Finish generating the next 6 quarter-keys.
672 *
673 * On entry xmm0 is r3:r2:r1:r0, xmm1 is stuff:stuff:r5:r4
674 * and xmm2 is stuff:stuff:X:stuff with X = rot( sub( r3 ) ) ^ RCON.
675 *
676 * On exit, xmm0 is r9:r8:r7:r6 and xmm1 is stuff:stuff:r11:r10
677 * and those are written to the round key buffer.
678 */
679 "1: \n\t"
680 "pshufd $0x55, %%xmm2, %%xmm2 \n\t" // X:X:X:X
681 "pxor %%xmm0, %%xmm2 \n\t" // X+r3:X+r2:X+r1:r4
682 "pslldq $4, %%xmm0 \n\t" // etc
683 "pxor %%xmm0, %%xmm2 \n\t"
684 "pslldq $4, %%xmm0 \n\t"
685 "pxor %%xmm0, %%xmm2 \n\t"
686 "pslldq $4, %%xmm0 \n\t"
687 "pxor %%xmm2, %%xmm0 \n\t" // update xmm0 = r9:r8:r7:r6
688 "movdqu %%xmm0, (%0) \n\t"
689 "add $16, %0 \n\t"
690 "pshufd $0xff, %%xmm0, %%xmm2 \n\t" // r9:r9:r9:r9
691 "pxor %%xmm1, %%xmm2 \n\t" // stuff:stuff:r9+r5:r10
692 "pslldq $4, %%xmm1 \n\t" // r2:r1:r0:0
693 "pxor %%xmm2, %%xmm1 \n\t" // xmm1 = stuff:stuff:r11:r10
694 "movq %%xmm1, (%0) \n\t"
695 "add $8, %0 \n\t"
696 "ret \n\t"
697
698 "2: \n\t"
699 AESKEYGENA(xmm1_xmm2, "0x01") "call 1b \n\t"
700 AESKEYGENA(xmm1_xmm2, "0x02") "call 1b \n\t"
701 AESKEYGENA(xmm1_xmm2, "0x04") "call 1b \n\t"
702 AESKEYGENA(xmm1_xmm2, "0x08") "call 1b \n\t"
703 AESKEYGENA(xmm1_xmm2, "0x10") "call 1b \n\t"
704 AESKEYGENA(xmm1_xmm2, "0x20") "call 1b \n\t"
705 AESKEYGENA(xmm1_xmm2, "0x40") "call 1b \n\t"
706 AESKEYGENA(xmm1_xmm2, "0x80") "call 1b \n\t"
707
708 :
709 : "r" (rk), "r" (key)
710 : "memory", "cc", "0");
711 }
712
713 /*
714 * Key expansion, 256-bit case
715 */
aesni_setkey_enc_256(unsigned char * rk,const unsigned char * key)716 static void aesni_setkey_enc_256(unsigned char *rk,
717 const unsigned char *key)
718 {
719 asm ("movdqu (%1), %%xmm0 \n\t"
720 "movdqu %%xmm0, (%0) \n\t"
721 "add $16, %0 \n\t"
722 "movdqu 16(%1), %%xmm1 \n\t"
723 "movdqu %%xmm1, (%0) \n\t"
724 "jmp 2f \n\t" // skip auxiliary routine
725
726 /*
727 * Finish generating the next two round keys.
728 *
729 * On entry xmm0 is r3:r2:r1:r0, xmm1 is r7:r6:r5:r4 and
730 * xmm2 is X:stuff:stuff:stuff with X = rot( sub( r7 )) ^ RCON
731 *
732 * On exit, xmm0 is r11:r10:r9:r8 and xmm1 is r15:r14:r13:r12
733 * and those have been written to the output buffer.
734 */
735 "1: \n\t"
736 "pshufd $0xff, %%xmm2, %%xmm2 \n\t"
737 "pxor %%xmm0, %%xmm2 \n\t"
738 "pslldq $4, %%xmm0 \n\t"
739 "pxor %%xmm0, %%xmm2 \n\t"
740 "pslldq $4, %%xmm0 \n\t"
741 "pxor %%xmm0, %%xmm2 \n\t"
742 "pslldq $4, %%xmm0 \n\t"
743 "pxor %%xmm2, %%xmm0 \n\t"
744 "add $16, %0 \n\t"
745 "movdqu %%xmm0, (%0) \n\t"
746
747 /* Set xmm2 to stuff:Y:stuff:stuff with Y = subword( r11 )
748 * and proceed to generate next round key from there */
749 AESKEYGENA(xmm0_xmm2, "0x00")
750 "pshufd $0xaa, %%xmm2, %%xmm2 \n\t"
751 "pxor %%xmm1, %%xmm2 \n\t"
752 "pslldq $4, %%xmm1 \n\t"
753 "pxor %%xmm1, %%xmm2 \n\t"
754 "pslldq $4, %%xmm1 \n\t"
755 "pxor %%xmm1, %%xmm2 \n\t"
756 "pslldq $4, %%xmm1 \n\t"
757 "pxor %%xmm2, %%xmm1 \n\t"
758 "add $16, %0 \n\t"
759 "movdqu %%xmm1, (%0) \n\t"
760 "ret \n\t"
761
762 /*
763 * Main "loop" - Generating one more key than necessary,
764 * see definition of mbedtls_aes_context.buf
765 */
766 "2: \n\t"
767 AESKEYGENA(xmm1_xmm2, "0x01") "call 1b \n\t"
768 AESKEYGENA(xmm1_xmm2, "0x02") "call 1b \n\t"
769 AESKEYGENA(xmm1_xmm2, "0x04") "call 1b \n\t"
770 AESKEYGENA(xmm1_xmm2, "0x08") "call 1b \n\t"
771 AESKEYGENA(xmm1_xmm2, "0x10") "call 1b \n\t"
772 AESKEYGENA(xmm1_xmm2, "0x20") "call 1b \n\t"
773 AESKEYGENA(xmm1_xmm2, "0x40") "call 1b \n\t"
774 :
775 : "r" (rk), "r" (key)
776 : "memory", "cc", "0");
777 }
778
779 #endif /* MBEDTLS_AESNI_HAVE_CODE */
780
781 /*
782 * Key expansion, wrapper
783 */
mbedtls_aesni_setkey_enc(unsigned char * rk,const unsigned char * key,size_t bits)784 int mbedtls_aesni_setkey_enc(unsigned char *rk,
785 const unsigned char *key,
786 size_t bits)
787 {
788 switch (bits) {
789 case 128: aesni_setkey_enc_128(rk, key); break;
790 case 192: aesni_setkey_enc_192(rk, key); break;
791 case 256: aesni_setkey_enc_256(rk, key); break;
792 default: return MBEDTLS_ERR_AES_INVALID_KEY_LENGTH;
793 }
794
795 return 0;
796 }
797
798 #endif /* MBEDTLS_AESNI_HAVE_CODE */
799
800 #endif /* MBEDTLS_AESNI_C */
801
